Crankshaft lapping machine



July 11, 1939. H. s. INDGE 2,166,009

CRANKSHAFT LAPPING MACHINE Filed July 20, 1938 4 Sheets-Sheet 2 25a 6? 252 wit 2"? F752 3mm HERBERT 5. INDG'E July 11, 1939. H. s. INDGE 2,156,009

CRANKSHAFT LAPPING MACHINE Filed July 20, 1938 4 Sheets-Sheet 3 llllll 232 IJZ gram

HERBERT 5'. INIJG'E July 11, 1939.

H. s; INDGE CRANKSHAFT LAPPING MACHINE Filed July 20, 1938 4 Sheets-Sheet 4 HERBERT 5. IND-GE Patented July 11, 1939 UNITED STATES PATENT OFFICE CRANKSHAFT LAPPING MACHINE Application July 20, 1938, Serial No. 220,283

11 Claims.

The invention relates to abrading machines, and more particularly to a crankshaft lapping machine.

One object of the invention is to provide a simple and thoroughly practical lapping machine for simultaneously lapping or polishing a plurality of cranks on a chankshaft. A further object of the invention is to provide a crankshaft lapping machine in which all of the crankpins and main bearing surfaces on a crankshaft may be simultaneously lapped. Another object of the invention is to provide a lapping machine for simultaneously lapping the crankpins on a crankshaft, in which a plurality of lapping arms are provided, each being independently and hydraulically operated and controlled. A further object of the invention is to provide a crankshaft lapping machine for simultaneously lapping all of the crankpins on a crankshaft, in which a time control mechanism is provided to stop the lapping operation after the crankshaft has been rotated a predetermined number of rotations.

A further object of the invention is to provide a plurality of main bearing and crankpin lapping arms on a pivotally mounted support which may be swung to and from an operating position. A further object of the invention is to provide a fluid pressure control mechanism for simultaneously moving all of the crank and main bearing lapping arms to and from an operating position. Other objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts, as will be exemplified in the structure to be hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings in which is shown one of various possible embodiments of the mechanical features of this invention,

Fig. 1 is a front elevation of the improved crankshaft lapping machine;

Fig. 2 is an end elevation, on an enlarged scale, of the improved crankshaft lapping machine;

Fig. 3 is a diagrammatic illustration of the hydraulic actuating mechanism and the piping therefor; 50 Fig. 4 is a vertical sectional view through the control valve and vane motor, with the valve shown in position to operate the arm clamping mechanism;

Fig. 5 is a similar vertical sectional view through the control valve and vane motor, showing the valve in position to open the lapping element into an inoperative position;

Fig. 6 is a fragmentary sectional viewtaken approximately on the line 6-6 of Fig. 2, showing the control valve, vane motor, and the lapping arm clamping mechanism actuated thereby;

Fig. '7 is a fragmentary end elevation, on an enlarged scale, of a lapping arm and the supporting and clamping arrangement for the same;

Fig. 8 is a fragmentary sectional view, on an enlarged scale, taken approximately on the line 8-8 of Fig. 6;

Fig. 9 is a fragmentary view of the clamp actuating mechanism as shown in Fig. 8 in a locked position;

Fig. 10 is a fragmentary sectional view of the lapping arm clamping mechanism, on an enlarged scale, taken approximately on the line l0l0 of Fig. 8;

Fig. 11 is a fragmentary cross sectional view, taken approximately on the line llll of Fig. 7;

Fig. 12 is a fragmentary cross sectional view, on an enlarged scale, taken approximately on the line l2-'l2 of Fig. '7, showing the bearing for pivotally supporting the lapping arm;

Fig. 13 is a cross sectional view, on an enlarged scale, through the vane type motor, taken approximately on the line l3l3 of Fig. 6; and

Fig. 14 is a fragmentary cross sectional view, taken approximately on the line l4l4 of Fig. 13.

A crankshaft lapping machine has been illustrated in the drawings comprising a base 20 which supports a longitudinally reciprocable work supporting table 2|. Table ways are provided between the base 20 and the table 2| which in the preferred form are of an anti-friction type. The base 20 is provided with a plate 26 which is fixed to the base and is provided at its edge portions with grooves 21 and 28 which serve as an inner raceway for a pair of spaced rows of antifriction balls 29 and 30, respectively. A cage is provided between the races to space the balls 29 and 30 longitudinally, as desired. This construction forms an anti-friction way whereby the table 2| together with a headstock 22 and a footstock 23 may be readily reciprocated during the lapping operation.

Headstoclc The headstock 22 is provided with a rotatable spindle 33 which is supported in bearings (not shown). The headstock spindle 33 may be rotated from any suitable source of power, such as an overhead belt drive, or a self-contained electric motor. In the preferred construction an electric motor 34 is mounted on the base 20 of the machine. The motor 34 is provided with a driving pulley 35 which is connected by multiple V-be1ts 35 with a pulley 31 on the headstock 22. The headstock construction has not been illustrated in detail in the present application since this headstock is not considered to be a part of the present invention and, furthermore, is identical with that shown in our prior United States Patent No. 2,092,734 dated September 7, 1937, to which reference may be had for details of disclosure not found herein.

Table reciprocation In the lapping of the crankpins and main bearings of an automobile crankshaft, it is desirable to provide a relative reciprocatory movement between the work piece and the abrading element to prevent production of grain markings on the surface of the work piece. In the present case, the work table 2| is arranged for a longitudinal reciprocatory movement which is preferably accomplished by a translation of the rotary motion of the headstock spindle 33 into a reciprocatory movement of the table 2I. The specific mechanism for reciprocating the table has not been illustrated in the present case, since this mechanism is identical with that shown in the abovementioned prior patent, to which reference may be had for details of the table reciprocating mechanism not found herein.

Foofstock The other end of the crankshaft 24 is supported by the footstock 23 which is provided with a footstock center 5| which is carried by a rotatable spindle 52. The spindle 52 is journalled in bearings 53 and 59 within a hollow slidably mounted sleeve 55. The sleeve 55 is slidably keyed by means of a key 56 within an aperture 51 in the footstock frame.

A fluid pressure actuating mechanism is provided to move the footstock center 5I rapidly to and from an operative position to support one end of a crankshaft 24 within the machine. This mechanism comprises a fluid pressure cylinder 58 having a slidably mounted piston 59 contained therein. The piston 59 is connected to one end of a piston'rod 69, the other end of which is connected to a pin 5|. The central portion of the pin9I is slabbed off on opposite sides so as to slide within an elongated slot 62 formed at the lower end of the piston rod 69. The pin BI serves as a central pivotal connection between a pair of toggle levers 63 and 64. The toggle lever 64 is connected to the footstock frame 59 by means of a stud 55. The end of the toggle lever 63 is connected by a stud 65 with a slidably mounted sleeve 91 which slides within an aperture 68 within the sleeve 55. The sleeve 51 is held against rotation by means of a pin 69 which is carried by the sleeve 55 and rides within an elongated slot in the sleeve 55. A spring I9. is contained within the sleeve 61 and is interposed between the end of the sleeve 51 and a thrust collar H.

When fluid under pressure is admitted through a pipe I2 to a cylinder chamber I3, the piston 59 is moved downwardly and the toggle levers 63 and 64 are moved from the dotted line positions 63a and 84a into the full line positions 63 and 64 (Fig. 2) which serves to move the sleeve 51 into the position illustrated which in turn serves tocompress the spring I9 and, through the connecting parts, moves the sleeve 55 and footstock center 5| into operative supporting engagement with the end of the crankshaft 24.

During this movement, fluid is exhausted from a cylinder chamber I4 and through a pipe I5. The admission to and exhaust of fluid from the footstock operating cylinder 58 will be hereinafter described. This footstock is identical with that shown in the prior United States Patent No. 2,117,960 dated May 17, 1938 to which reference may be had for details of disclosure not contained herein.

Lapping arm support It is desirable to provide a movable support for a plurality of crankpin and bearing lapping arms so that they may be simultaneously and quickly moved into an operating or an inoperative position, as desired. A pair of spaced supporting arms 89, only one of which has been illustrated in the drawings v(Fig. 2), are mounted on a rock shaft 8I which is supported in bearings on the rear of the machine base 20. The arms 89 are provided with horizontally extending portions which are connected by two spaced bars 82 and 83 which serve as slide bars or ways for supporting a plurality of lapping arms to be hereinafter described.

The lapping arm assembly supported by the arms 89 is arranged so that they may be automatically moved to and from an operating position to facilitate loading of crankshafts into the machine and removing them therefrom after a lapping operation has been completed. In order to move the entire lapping assembly to an inoperative position, a fluid pressure mechanism is provided including a fluid pressure cylinder 84 which is pivotally connected by means of a stud 85 within the base 29 of the machine. A piston 86 is slidably mounted within the cylinder 84 and is connected to one end of a piston rod 81. The other end of the piston rod 81 is connected by a stud 88 with an arm 89 pivotally mounted on a shaft 99 supported within the base 29. The arm 89 is provided with a stud 9I which is connected to one end of a link 92. The other end of the link 92 is connected by a stud 93 with the adjacent ends of a pair of toggle levers 94 and 95. The toggle lever 94 is connected at its other end by means of a stud 96 with the base 29, and the toggle lever is connected by a stud 91 with an arm 98 which is fixedly mounted on the rock shaft 8! and is arranged to rock the shaft 8| together with the arms 89 and all of the crankpin and bearing lapping arms together with their supporting and actuating mechanisms either into or away from an operative position.

The levers 89, 92, 94 and 95, as shown in full lines in Fig. 2, are in a position to hold the arms 98 and 89 together with the entire lapping arm assembly in an operating position. After a lapping-operation has been completed, fluid under pressure is admitted to the cylinder 84 to cause the piston 88 and piston rod 81 to move toward the right (Fig. 2) and to shift the levers 89, 92, 94 and 95 and arm 98 into the dotted line positions 88a, 93a, 94a, 95a and 98a. This movement serves to rock the arms 80 in a clockwise direction (Fig. 2) to move the entire lapping arm assembly to an inoperative position.

A fluid pressure system is provided to control the admission of fluid under pressure to the cylinder 84. A pump 99 within the base 29 of the machine draws fluid through a pipe 99a from a reservoir I99 within the base 29 and passes fluid under pressure through a pipe II" to a reverse: or control valve I92. The valve I92 is of a balanced piston type having a valve stem I93 which is provided at its outer end with a spool-shaped member I04 and is connected by means of a pair of diametrically opposed studs or pins I05 mounted on a yoked end of acontrol lever I06. The control lever I06 is pivotally supported .on a stud I! which is carried by a bracket I08 fixedly supported on the base 20 of the machine. A plurality of valve pistons I09, H0 and III are formed integral with the valve stem I03. Fluid under pressure passing through the pipe IOI passes into a valve chamber II3 located between the valve pistons H0 and III and passes out through a pipe I I4 into a cylinder chamber I I5 to cause the piston 86 to move toward the left (Figs. 2 and 3) to shift the lapping arm supports 80 in a counterclockwise direction (Fig. 2) to position the crankpin and bearing lapping arms in an operating position.

During the admission of fluid under pressure to the cylinder chamber II5, fluid is exhausted from a cylinder chamber I I6 at the other end of the cylinder 84, through a pipe III, through a valve chamber II 8 located between the valve pistons I09 and H0, and out through a pipe II9 into the reservoir I00. A fluid pressure relief valve I20 is connected by a pipe I 2I with the pipe IOI and serves to by-pass any excess fluid if the pressure within the pipe line IOI for any reason increases over a desired and predetermined pressure.

The control valve I02 also serves to control the admission of fluid to the footstock cylinder 50. The pipe I2 is connected to the pipe H4 and serves to convey fluid under pressure to the cylinder chamber I3 simultaneously with the passage of fluid under pressure to the cylinder chamber H5 in the cylinder 84. The pipe I5 connects the cylinder chamber I4 of the cylinder 58 with the pipe I I I so that in the position of the control valve I02 as shown in Fig. 3, fluid will exhaust simultaneously from the cylinder chamber I4 in the cylinder 58 and from the cylinder chamber H6 in the cylinder 84.

When the control valve I02 is shifted into the position illustrated in Fig. 3, fluid under pressure simultaneously enters both the cylinder 58 and the cylinder 84, and due to the fact that less power is required to move the footstock than the lapping arm assembly, the footstock center moves first into an operative position, after which the lapping arm assembly moves into an operative position adjacent to the portions of the work to be lapped.

Lapping arms In order that all of the crankpins and main bearings on the crankshaft 24 may be simultaneously lapped, a plurality of crankpin and bearing lapping arms are provided which correspond in number with the crankpins and bearings to be lapped. As illustrated, there are three main bearing lapping arms I30, I3I and I32. There are four crank lapping arms I33, I34, I35 and I36 which are supported in spaced relationship with each other so as to simultaneously engage and lap the three main bearings and the four crankpins on the crankshaft 24.

The bearing lapping arms and crankpin lapping arms are substantially identical in construction and differ in operation only in the fact that the bearing lapping arms are stationary while lapping the bearing surfaces which are concentric with the axis of rotation of the crankshaft 24, whereas the crankpin lapping arms are rocked during the lapping operation due to the fact that they engage a crankpin which revolves about the axis of rotation of the crankshaft 24.

A side elevation of the lapping arm I32 is shown in Fig. 2. The lapping arm I32 as well as all of the other lapping arms are each provided with a pair of pivotally mounted lap supporting arms I40 and MI which are provided at their operating ends with partially cylindrical lap supporting blocks I42 and I43, respectively. The arms I40 and MI are pivotally supported by the studs I44 and I45 on the lapping arm I32. The other ends of the arms I40 and II are connected by a pair of toggle levers I46 and I4! which are connected together at their inner ends by means of a stud I48 which slides in elongated slots I49 in the side plates of the lapping arm I32. When the toggle levers I46 and M1 are in a straightline position, as indicated in Fig. 2, the lap supporting members I42 and I43 are maintained in operative engagement to hold the abrasive or lapping element in operative contact with the work piece 24.

In the preferred construction, the lap arms I40 and I4! are arranged to be automatically moved into and away from an operative position and in the preferred construction a hydraulically operated mechanism is provided for actuating the same. A fluid pressure cylinder I32a is mounted on the upper end of the lapping arm I32. A piston I32b is slidably mounted therein and is con nected to one end of a piston rod I320. The other end of the piston rod I320 is connected by a stud i50. A link I5I is connected at one end to the stud I50 and at the other end to the stud I48 which pivotally connects the toggle levers I46 and I4'!. It will be readily apparent from the foregoing disclosure that when the piston 83211 is moved downwardly, that is, toward the left (Fig. 2), the piston rod I320 and the connecting link I5I will be moved also in a downward direction toward the left which serves to unlock the toggle levers I46 and I4! and thereby to rock the lap arms I40 and I42 together with the lap supporting elements I42 and I43 to an inoperative position out of engagement with the bearings of the crankshaft 24. When fluid under pressure is passed through a flexible pipe I320Z, into a cylinder chamber I326, the piston I321) will be moved upwardly to move the toggle levers I46 and I41 into the position shown in Fig. l to move the abrasive lapping element into an operating position in engagement with the work piece 24 for a lapping operation. Similarly, when the fluid under pressure is admitted through a flexible pipe I32 to cause a downward movement of the piston I321) toward the left (Figs. 2 and 3), the toggle levers I46 and I41 will be unlocked to move the lappingelement to an inoperative position. It should be noted in the drawings (Fig. 3) that each one of the lapping arms is provided with an independent fluid operated piston and cylinder as well as piston rods which have been designated in the diagram with the same reference numeral as the lapping arm on which it is mounted, the cylinders being designated by the small letter a, the pistons by the small letter 12, and the piston rods by the small letter 0.

It is desirable that all of the lapping elements represented by the supporting members I42 and I43 (Fig. 2) be moved into or away from an operating position simultaneously. This is preferably accomplished by providing a pair of longitudinally extending pipes or manifolds I53 and I 54 which are fixedly supported on the spaced arms 80 and serve as a common source of fluid under pressure which may be forced either through the flexible pipe i32d to move the lapping element into an operating position or when the fluid under pressure is reversed, to flow through the flexible pipe I321 simultaneously to move all of the lapping elements to an inoperative position after a lapping operation has been completed. The admission to and exhaust of fluid from the manifolds or pipes I53 and I54 is controlled by a valve mechanism to be hereinafter described.

Each of the lapping arms I30 to I36 inclusive is pivotally supported. The details of support for these arms being identical, only one has been illustrated in detail. An arm I55 is pivotally mounted on a supporting member I55 which is clamped in adjusted position on the guide rods 82 and 83. The lower end of the arm I55 is pivotally connected to the supporting member I56. A yoked end portion of the lever I55 straddles the supporting member I53 and is supported by a bushing I51 which passes through an aperture in the supporting member I56 and also through apertures within the opposite portions I58 and I59 of the yoked portion of the arm I55 (Fig. 12). To facilitate taking up lost motion between the yoked member and the supporting member I55, a nut and screw mechanism is provided comprising a screw I00 having a flanged nut IEI which is screw threaded onto the screw I50 and fits within a recess I62 in the portion I58 of the yoked member. Similarly, a nut I63 is screw threaded onto the screw I63 and its outwardly extending flanged portion fits within a recess I54 in the portion I59 of the yoked end of the arm I55. By adjusting the flanged nuts ISI and IE3, the yoked portions I58 and I59 may be adjusted relative to the supporting member I55. In order to maintain the parts in adjusted position, each of the flanged nuts I62 and I33 is serrated on the peripheral surface of the flange, as indicated in Fig. 7 and screws I35 and I56 are provided to lock the flanged nuts in adjusted position.

A similar pivotal connection is provided between the upper end of the arm I55 and the lapping arm I32 supported thereby. This pivotal connection is identical in construction with that shown for the lower end, as illustrated in Figs. 7 and 12, and consequently has not been illustrated in detail. By providing a pivotal connection between the supporting member I55 and the arm I55 and also between the arm I55 and the lapping arm I32, the lapping arm is free to move and to follow the crankpin 24 in its revolving movement to lap the peripheral surface thereof. All of the lapping arms, both the main bearing lapping arms I 30, I3I and I32, as well as the crankpin lapping arms I33, I34, I35 and I36, are mounted in the same manner as that described above.

A flexible abrasive paper or cloth is preferably utilized as a lapping means. Each of the lapping arms is provided with a separate strip of continuous abrasive paper which Wraps around the crankpin or main bearing and is held in position thereagainst by the lap supporting members I42 and I43. A rod I10 is supported on the rear of each supporting member I55 by means of a bracket HI and serves as a support for a reel I12 of flexible abrasive paper I13. The abrasive paper passes through guides I14 and I15 supported on the under side of the supporting member I55 and passes through a series of rollers I15 carried by a bracket I11 which is in turn supported on the lap supporting arm I4 I. The abrasive paper as above described wraps around the crankpin 24 and is supported by the lap supporting members I43 and I42 and is wound up on a reel I18 which is supported by a stud I19 carried by a bracket I which is supported to move with the lap supporting arm I40.

In the preferred construction the lap supporting members I42 and I43 are mounted so that they may float or move relative to the supporting arms I40 and I4I so that the lap supporting members I42 and I43 are self-aligning when brought into operative position to support the abrasive paper on the pin or bearing for a lapping operation. The brackets I11 and I80 in the preferred form are fixedly mounted to the floating lap supporting members I42 and I43. A holding pawl I8! cooperating with the ratchet wheel end of the reel I18 serves to prevent unreeling of the worn paper wound up on the reel I18. As illustrated in the drawings, the paper is fed manually when desired by the operator by turning the reel I18. Only one of the reels I18 and the associated parts to guide the abrasive paper through to the reel I18 have been illustrated in detail. Each lapping arm is provided with similar equipment supported on a separate supporting member I55. The abrasive paper and the wind-up reels for each lapping arm are illustrated in the front elevation of the machine shown in Fig. 1. The lappingarm I30 is supplied with a strip of abrasive paper I which is wound up upon a reel I80. The lapping arm I33 is provided with a strip of abrasive paper I81 and the used portion thereof is Wound up on a reel I38. The lapping arm I34 is supplied with a strip of abrasive paper I03, the used portion of which is wound up on a reel I90. supplied with a strip of abrasive paper I9I, the used portion of which is wound up on a reel I92. The arm I35 is supplied with a strip of abrasive paper I33, the used portion of which is wound up on a reel I84, and the lapping arm I35 is supplied with a strip of flexible abrasive paper I05, the used portion of which is wound up on a reel I06. Inasmuch as the abrasive paper supporting reels and the guiding means are identical for each of the lapping arms, only one of these mechanisms has been completely illustrated, as shown in Fig. 2.

It is desirable to provide a guiding and locking means for guiding the lapping arms during their swinging movement as they follow the revolving crankpins and to look all of the arms in their indexed position before the lap supporting members I42 and I43 are released from operative position and the head swung to an inoperative position to facilitate loading of the machine. It is desirable to provide such a locking device so that when the members 80 are moved to an operating position after a new crankshaft has been loaded into the machine, all of the arms will be in proper indexed position so that the lap supporting members I42 and I43 may be automatically brought into engagement with the pins and bearings of the crankshaft 24.

In order that the lapping elements may be guided in their swinging movement and held against lateral movement during the reciprocation or oscillation of the crankshaft during the lapping operation, a pair of guiding plates 200 and 20I are fixedly supported on the supporting bracket I56 and are spaced apart by a distance equal to the thickness of the lapping arm I32 and are provided with sufficient clearance so that the arm I32 is guided thereby and is held against lateral movement by the guiding plates 200 and 20 I. The lapping arm I30 is similarly guided by the guiding plates 202 and 203.

The lapping arm I3I is The lapping arm I33 is 75 guided by the guiding plates 204 and 205. The lapping arm I34 is guided by the guiding plates 206 and 201. The lapping arm I3I is guided by the guide plates 208 and 209. The lapping arm I35 is guided by the plates 2H) and 2| I, and the lapping arm I36 is guided by the plates 2I2 and 2 I3.

In order to provide a means for simultaneously clamping all of the arms in their operative indexed positions, the guide plates 202, 204, 205, 208, 2), 2I2 and 200 are each provided with a groove or guideway 2I4 which supports a slidably mounted member 2I5 having cam surfaced depressions 2I6 formed therein. The guiding plate 200 is provided with a pair of cams 2H and 2! which engage the cam shaped depression 2I6 formed in the slidably mounted member 2I5. It will be readily apparent that if the slide 2I5 is moved upwardly (Fig. 6) relative to the guiding plate 200, the cam depressions 2 I 5 engaging the fixed cams 2H and 2I8 will cause the slide member 2I5 to move toward the right (Figs. 6 and 10) and thereby bind or clamp the arm I 32 in fixed position relative to the guiding plates 200 and 20 I A spacing block 2I9 serves to hold the slide member 2I5 in position and a spring 220 carried by the block 2 I 9 serves to exert a pressure toward the left tending to hold the slide 2I5 within its supporting groove or slideway 2I4. Each of the lapping arms I30 to I36 inclusive is provided with identical clamping means, consequently only one of these clamps has been illustrated in detail. The guide plate 202 is provided with a clamping slide 202a and the guiding plate 204 is provided with a clamping slide 204a,. The guide plate 206 is provided with a clamping slide 206a and the guide plate 208 is provided with a clamping slide 20811. The guide plate 2! is provided with a clamping slide 2I0a, and the guide plate 2I2 is provided with a clamping slide 2I2a.

In order simultaneously to clamp all of the lapping arms, it is desirable to provide a suitable means for simultaneously actuating the clamping slide 2I5, 202a, 204a, 206a, 208a, 2I0a and 2I2a. As illustrated in the drawings, a shaft 22I is rotatably supported in apertures in the guiding plates 200 to 2I2 inclusive. Each of the clamping slides is provided with an elongated slot 222 (Fig. 8). The shaft 22I carries an eccentric 223 which rides within the elongated slot 222. When the shaft 22I is rotated, the eccentric 223 rotating within the elongated slot 222 causes the slide 2I5 to move upwardly to move the lapping arm I32 in clamped position between the guide plates 200 and 20I. The shaft 22I is provided with a plurality of eccentric members corresponding to eccentric 223 each of which is arranged to engage elongated slots in the respective slides 202a, 204a, 206a, 208a 2I0a, and 2I2a.

A vane type fluid pressure motor 230 is provided for rocking the shaft 22I to clamp and release the lapping arms. The motor 230 is provided with a shaft 23I which supports a rotary vane 232. The rotor shaft 23I projects from the motor casing toward the left (Fig. 6). An arm 233 is supported on the rotor shaft 23I and is provided with a projection 234 which is arranged in the path of opposed screws 235 and236 (Fig. 7) which are carried by bosses 231 and 238, respectively, which are formed integral with an arm 239 which is fixedly clamped to the shaft 22 I.

It will be readily apparent from the foregoing disclosure that when fluid under pressure is caused to actuate the rotor or vane 232 of the fluid mtor 230, the projection 234 will move either in a clockwise or-counterclockwise direction to engage either the screw 235 or the screw 236 to rotate the shaft 22I and through the eccentrics 223 above described will cause the clamping slide 2I5 and the other corresponding slides to move either into a clamped or released position, depending upon the direction of rotation of the fluid motor 230.

In order to attain one object of the invention, a control valve is provided for controlling the admission to and exhaust of fluid from the lap actuating cylinders and the rotary vane type motor 230 for clamping the lapping arms in their respective indexed positions. A control valve 250 is provided which is arranged so that before the lapping members may be opened, the lapping arms are clamped in their respective positions and similarly before the clamp can be released, fluid is admitted to move the lapping elements into operative position. Fluid under pressure passing through the pipe IUI passes through the pipe 25I to the control valve 250. The control valve 250 is preferably a rotary type valve having a valve rotor 252 which is actuated by a control lever 253. Fluid under pressure passing through the pipe 25I enters a valve chamber 254 in the position shown in Fig. 3 and passes out through a pipe 255 into the manifold I53 so as to cause all of the pistons I301), I3Ib, I322), I331), I341), I351; and I36b to close all of the lapping elements in operative position in engagement with the pins and bearings on the crankshaft 24 to be lapped. Fluid under pressure also passes through the passage 256 into a chamber 251 to shift the clamping motor vane 232 into the position illustrated in Figs. 3 and 13 to unclamp all of the lapping arms so that the crankshaft 24 may be rotated and all of the main bearings and the crankpin bearings lapped to the desired extentr After the lapping operation has been completed, the control lever 253 is shifted into position 253a (Fig. 2) which shifts the valve into the position illustrated in Fig. 4 so that fluid under pressure entering the valve chamber 254 is still applied through pipe 255 to hold the lapping elements in an operative closed position and at the same time passes through a passage 258 into a motor chamber 259 to cause the vane 232 to shift into the position illustrated in Fig. 4 so as to actuate the clamp and thereby clamp the lapping arms in a fixed indexed position. The lever 253 may then be shifted into position 253%) (Fig. 2) which serves to shift the valve 252 into the position illustrated in Fig. 5 so that fluid passing through the pipe 25! into the valve chamber 254 passes not only through the passage 258 to hold the lapping arms clamped in an indexed position but also passes out through a pipe 260 which is connected to the manifold I54 and serves to admit fluid under pressure to the upper ends of the cylinders I30 to I36 inclusive to open the lapping elements so that the entire lapping arm assembly may be moved to an inoperative position. The valve 252 is provided with an exhaust chamber 26I which connects with a pipe 262 to return exhaust fluid to the reservoir I00. When the valve 252 is in the position illustrated in Fig. 3, fluid is exhausted from the motor chamber 259 and also from the upper cylinder chambers in the lapping arms through the manifold I54. Similarly, when the valve 252 is shifted into the position illustrated in Fig. 5, fluid under pressure is exhausted from the chamber 251 and also from the lower cylinder chamber in each of the lapping arm cylinders through the manifold I53, pipe 255, into Valve chamber 261, and out through the exhaust pipe 262 into the reservoir I00.

A pivotally mounted link 265 is mounted on the end of the control lever 253 and is provided with a stud 266 which rides within an arcuate slot 261 in the plate 263. Three notches are provided in the lower surface of the arcuate slot 267 so that the stud 265 may readily locate the lever 253 in position so that the valve 252 corresponds to the position illustrated in Fig. 3, or in position 253a so that the valve 252 assumes the position illustrated in Fig. l, or in the position 253?) with the valve 252 in the position illustrated in Fig. 5.

The operation of this improved lapping machine will be readily apparent from the foregoing disclosure. Assuming all of the adjustments to have been previously made, the operator places a crankshaft 2'4 to be'l'apped on the loading cradles 'or brackets 2T0 and 2H and rolls it into alignment with the headstock and footstock centers. The control lever I06 is then moved in a clockwise direction (Figs. 2 and 3) first to shift the valve I02 to admit fluid to the footstock cylinder 58 so that the footstock center 5'! moves the crankshaft 2'4 into an operative position whereby it is supported by the headstock and footstock centers and at the same time fluid is admitted to the cylinder 34 to shift the arms it supporting the entire lapping arm assembly into an operative position with the lapping 'elements adjacent to a crankshaft 24 to be lapped. The control lever 253 is in position 2153b when the crankshaft is. loaded into the machine. The lever 253 is then shifted from position 2531) into position 253a which serves to close the lap supporting blocks M2 and M3 to hold the abrasive paper H3 in operative lapping engagement with all of the main bearing and crankpins on the crankshaft 24. The lever 253 is then shifted from position 253a into 'full "line position (Fig. 2) to unclamp the lapping arrns, after which the headstock 22 may be set in motion to rotate the crankshaft 24 and reciprocate or oscillate the table or support 21 simultaneously to lap all of the main bearings and crankpins on the crankshaft 24. After the lapping operation has been completed, the rotation of the headstock 22 is stopped automatically, as disclosed in the prior patent above referred to, after which the lever 253 is shifted through position 253a into position 2531), first to clamp all of the lapping arms in indexed positions, and then to open the supporting members I42 and M3. After this the control lever H36 may be shifted from the full line position, that is, in 'a counterclockwise direction, into the dotted line-position as indicated in Fig. 2 to admit fluid under pressure to withdraw the footstock center "5| and to 'move the entire lapping arm assembly to an inoperative position.

It will thus be seen that there has been provided by this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made 'of the above invention and as. many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In a crankshaft lapping machine having a pltuality of lapping arms, a movable frame to support said lapping arms, clamping mechanism for clamping said lapping arms relative to said frame, a rotatable work support including a headstock and footstock, a plurality of fluid pressure motors respectively connected to said footstock, said frame, said lapping arms and said clamping means, a manually operable control valve operatively connected to control the flow of fluid under pressure to and from said footstock motor and said frame motor, and a second control valve on said frame for controlling the flow of fluid under pressure to and from said lapping arm motor and clamping motor.

2. In a crankshaft lapping machine, a plurality of crankpin and bearing lapping arms each having a pair of opposed lap supporting members, a pair of toggle levers on each of said arms, a piston and cylinder on each of said arms to actuate said levers to move said members to and from an operative position, a movable frame to support all of said lapping arms for movement to and from an operative position, a piston and cylinder to move said frame, a clam-ping mechanism to clamp all of said arms in an indexed position relative to said frame, means including a fluid motor to actuate said clamp, and a manually operable control valve to control the fluid flow to said arm cylinders and said clamp motor, said valve being arranged simultaneously to admit;

fluid to said arm cylinders to move the lap supporting members simultaneously into operative position and then to admit fluid to said clamp motor to unclamp the lapping arms.

3. In a crankshaft lapping machine, a base, a

movable frame thereon, means including a fluid pressure piston and cylinder to move said frame to and from an operative position, a longitudinally movable Work supporting table, a rotatable work support on said table including a headstock and a footstock, a fluid pressure piston and cylinder to actuate said footstock, a fluid pressure system including a control valve simultaneously to control the admission to and exhaust of fluid to and from said frame cylinder and said footstock cylinder, a plurality of crankpin and bearing lapping arms on said support which are arranged simultaneously to engage and lap all of the cran-kpins and bearings on a crankshaft, lapping elements carried "by eachrof said arms, a fluid pressure piston and cylinder on each of said arms which are arranged to actuate said lapping members, a clamping device for each of said arms including a rotatable cam and a slide, means including a vane type fluid motor simultaneously to rotate said cams to clamp and release said arms, and a control valve simultaneously to admit fluid to said arm cylinders to clamp the arms .in an indexed position and to move each of said lapping members to an inoperative position.

4. In a crankshaft lapping machine, a base, a pivotal-1y supported frame thereon, means including a fluid .pressure piston and cylinder to move said frame to and from an operative position, a longitudinally movable work supporting table on said base, means .to reciprocate or oscillate said table, a rotatable work support on said table including a motor driven headstock and a footstock, a fluid pressure piston and'cylinder 1 pin and bearing lapping arms on said support, a pair of opposed lap supporting members on each of said arms, a pair of toggle levers on each of said arms which are arranged to actuate said members, a fluid pressure piston and cylinder on each of said arms to actuate said toggle levers, a plurality of clamping devices on said frame, each device being arranged to lock one of said arms in an indexed position during the loading operation, a cam associated with each of said locking devices, a shaft supporting said cam, a rotary fluid motor to rotate said shaft to clamp or release said arms, and a manually operable control valve simultaneously to admit fluid to said motor to clamp all of said arms in an index position and to admit fluid under pressure to the cylinder on each of said arms to open the lap supporting members.

5. In a crankshaft lapping machine having a movable lapping arm, a frame to support said arm, a pair of spaced parallel guides on said frame for guiding said arms, a clamping device to clamp said arm in a fixed position relative to said frame including a rotatable cam, a rotatable shaft to support said cam, a vane type rotary fluid operated motor supported on one of said guides and having its vane connected directly to said shaft to rotate said cam and clamp or release said lapping arm.

6. In a crankshaft lapping machine having a plurality of crankpin and bearing lapping arms, a frame pivotally to support said arms, a plurality of spaced parallel guides on said frame for guiding each of said lapping arms, and a clamping device simultaneously to clamp all of said arms in an indexed position relative to said frame including a clamping member movably supported on said guides, a rotatable cam associated with each pair of guides to actuate said clamping member relative to said guides, a fluid motor operatively connected simultaneously to rotate all of said cams to clamp or release said lapping arms.

7. In a crankshaft lapping machine having a plurality of crankpin and bearing lapping arms, a movably mounted frame to support all of said arms, pivotal connections between said arms and frame, a pair of spaced parallel guides on said frame for guiding each of said arms, and a clamping device simultaneously to clamp all of said arms in an indexed position relative to said frame including a slide supported on the inner face of one of each of the pairs of guides, a cam between said slide and guide, means including a rotatable cam to move each of said slides relative to its supporting guide so that the first cam causes the slide to clamp the lapping arms relative to the guides, a rotatable shaft supported in bearings on said guides to support all of said rotatable cams, and a vane type rotary fluid motor to rotate said shaft and cams simultaneously to clamp or release all of the lapping arms.

'8. In a crankshaft lapping machine having a 'movable lapping arm, a frame pivotally to support said arm, a pair of spaced parallel guides on said frame for guiding said arm, and a clamping device to clamp said arm in a fixed position relative to said frame including a cam actuated slide supported on the inner surface of one of said guides, a rotatable cam supported by said guides and arranged to cause a relative movement between the slide and guides, and a fluid motor operatively connected to rotate said cam to move said slide and clamp or release said lapping arm.

9. In a crankshaft lapping machine, a plurality of crankpin and bearing lapping arms each having a pair of opposed lap supporting members, a pair of toggle levers on each of said arms which are arranged to move said members to and from an operative position, a fluid pressure piston and cylinder on each of said arms to actuate said levers, a clamping device associated with each of said arms and arranged to clamp all of said arms in an indexed position during the loading operation, means including a fluid motor simultaneously to actuate said clamping device, and a control valve which is arranged to control the admission of fluid under pressure to said lapping arm cylinders and said fluid motor.

10. In a crankshaft lapping machine, a plurality of crankpin and bearing lapping arms arranged simultaneously to engage and lap all of the crankpins and bearings on said shaft, a pair of opposed lap supporting members on each of said arms, toggle levers on each of said arms which are arranged to actuate said members, a fluid pressure piston and cylinder on each of said arms which are operatively connected to actuate said toggle lever, a clamping device arranged to clamp each of said arms in an indexed position during the loading operation, a cam to operate each of said clamping devices, a fluid motor to rotate said cams to clamp or rerelease said arms, and a control valve which is arranged first simultaneously to admit fluid under pressure to all of said lap arm cylinders to close said lap supporting members and then to admit fluid under pressure to unclamp all of said lapping arms when the valve is actuated to initiate a lapping operation.

11. In a crankshaft lapping machine, a plurality of crankpin and bearing lapping arms arranged simultaneously toengage and lap all of the crankpins and bearings on said shaft, a pair said arms, toggle levers on each of said arms which are arranged to actuate said members, a

fluid pressure piston and cylinder on each of said arms which are operatively connected to actuate said toggle levers, a clamping device arranged to clamp each of said arms in an indexed position during the loading operation, a cam to operate said clamping devices, a vane type fluid motor to rotate said cams to clamp and release said arms, and a control valve which is arranged first to admit fluid pressure to said motor to clamp all of said armsin an indexed position and then simultaneously to admit fluid under pressure to said lapping arm cylinders to open said lap supporting members when the valve is shifted after a lapping operation has been completed.

HERBERT S. INDGE. 

